Proposed Changes to ASHRAE/IES Energy Standard Open for Public Comment

Sixteen proposed addenda to ANSI/ASHRAE/IES Standard 90.1-2010, Energy Standard for Buildings Except Low-Rise Residential Buildings, are open for public review until Sept. 16.

Among the proposed addenda are five changes related to HVACR-equipment efficiencies, including Addendum bp, which adds minimum efficiencies for evaporative condensers used in ammonia-based refrigeration systems and updates references to cooling-tower standards published by the Cooling Technology Institute.

“The scope of Standard 90.1 was expanded in the 2010 edition to cover many new building types, including supermarkets and cold storage warehouses,” Frank Morrison, committee member, said. “As part of this expanded scope, the 90.1 committee worked with stakeholders to establish minimum efficiencies for evaporative condensers often used in the ammonia refrigeration systems found in these facilities.”

Specifically, Addendum bp would help users to select energy-efficient evaporative condensers and encourage manufacturers to develop more energy-efficient designs. It is anticipated future editions would incorporate requirements for an independent, third-party thermal-performance certification program for evaporate condensers, which has proven successful for both open- and closed-circuit cooling towers.

The other addenda related to equipment efficiencies are:

• Addendum bi, which would harmonize the minimum energy efficiencies of three-phase air-cooled commercial air conditioners and heat pumps below 65,000 Btuh with the efficiencies adopted by the U.S. Department of Energy (DOE) for residential central air conditioners.

• Addendum bj, which would re-establish the product class for small-duct high-velocity air conditioners and heat pumps. The minimum energy-efficiency levels proposed are 11 seasonable energy-efficiency ratio (SEER) for air conditioners and 11 SEER/6.8 heating seasonal performance factor for heat pumps, which are identical to the efficiencies established by the DOE for single-phase residential small-duct, high-velocity products.

• Addendum bk, which would amend the minimum energy-efficiency requirements for standard-size packaged terminal air conditioners and raise the minimum energy-efficiency ratio to the same level as that of packaged terminal heat pumps. This new minimum efficiency would become effective Jan. 1, 2015.

• Addendum bo, which would modify service water-heating efficiency requirements for electric water heaters, heat-pump pool heaters, and oil-storage water heaters.

Also among the proposed changes is Addendum bh, which would modify interior space-by-space lighting-power-density (LPD) tables for a variety of purposes, according to Eric Richman, chair of the lighting subcommittee. This includes an adjustment to some space-type LPDs based on light-level design recommendations found in the 10th edition of The Lighting Handbook, published by the Illuminating Engineering Society.

Addendum bh also introduces a set of LPDs for spaces predominantly occupied by seniors in permanent-living facilities. The revision also adds several generic space-type listings, including for copy rooms and computer rooms.

Other addenda open for public review until Sept. 16 are ac, bg, bl, bn, bq, bt, bu, bv, bw, and bx.